Spoiler alert: This story contains details from tonight's Season 4 finale. There was no holding back in Episode 8/Season 4 of The Affair on Showtime. There were bad days, unexpected meetings, blasts from the past, and a huge, shocking development for one key character, as the time shifting story line kept viewers guessing until the big reveal. Alison Bailey (Ruth Wilson), the focus of the show, naturally had the worst of it. She meets a long-lost father, who…